Shimano
E-Tube Cockpit Junction Box - SM-EW90 A/B

Note: This reference is meant to be used as a guide for creating a Shimano Di2 drivetrain package. For further assistance please feel free to give us a call.

Battery and Wires:

Our Shimano Di2 packages are built for three standard configurations based on battery location and wire routing. First, you'll need to determine if your frame uses an internal or external battery mount, and whether the routing is either internal or external. Below is a guide for which battery, charger, mount, and junction boxes are required for your configuration.

Battery and Wire Configurations

Battery

Battery Charger

Battery Mount

Junction A

Junction B

External Battery

w/ External Routing

SM-BTR1

SM-BCR1

SM-BMR2

SM-EW90 A/B 3/5 port

SM-JC40

External Battery

w/ Internal Routing

SM-BTR1

SM-BCR1

SM-BMR2

SM-EW90 A/B 3/5 port

SM-JC41

Internal Battery

w/ Internal Routing

SM-BTR2

SM-BCR2

SM-EW90 A/B 3/5 port

SM-JC41

Battery Mounts:

The SM-BMR2 battery mount is available in three configurations -- Long External, Short External, and Long Internal. Both Long versions are to be mounted using the bottle cage mounts, while the Short version is designed for Di2-specific frames with either a chainstay or down tube mounting location.

Junctions:

There are two junctions needed for completing your Di2 build -- A and B. Junction A, SM-EW90, is located at the handlebars and available in both three- and five-port options. The three-port option is intended for standard shifting with a left and right hand shifter. If you have the intention of using Shimano's satellite sprint shifters, or a combination of time trial shifters and shifter/brake levers, the five-port junction box will be the necessary selection.

Depending on your frame specification, Junction B (SM-JC40 or SM-JC41) is located either internally or externally at the bottom bracket area. Accordingly, SM-JC41 is designed for frames with internal wire routing, while SM-JC40 is intended for external wiring options.

E-Tube Wires:

For your convenience, we've created wire packages for your Di2 build kit in the sizes Small, Medium, and Large. Below, you'll find which wire lengths are included in each kit. Additionally, we've recommended a kit size based on your frame size.

Always at your fingertips.

The Shimano E-Tube Cockpit Junction Box works with the Dura-Ace Di2 9070 groupset to enable supplemental shifting positions so that the ease of electronic shifting is always at your fingertips, no matter what hand position you favor.

The E-Tube mounts just below your handlebars and functions as a junction box so that no additional wiring is needed to add a second set of shifters to your bars. Now you can keep your hands in the drops to maximize aerodynamics on long, flat stretches and up high for greater control. And for even more options, the E-Tube Cockpit Junction Box comes in two configurations: a three port and five port. To keep you running, both versions feature a charging port for the new internal Di2 battery.

Size chart

Note: This reference is meant to be used as a guide for creating a Shimano Di2 drivetrain package. For further assistance please feel free to give us a call.

Battery and Wires:

Our Shimano Di2 packages are built for three standard configurations based on battery location and wire routing. First, you'll need to determine if your frame uses an internal or external battery mount, and whether the routing is either internal or external. Below is a guide for which battery, charger, mount, and junction boxes are required for your configuration.

Battery and Wire Configurations

Battery

Battery Charger

Battery Mount

Junction A

Junction B

External Battery

w/ External Routing

SM-BTR1

SM-BCR1

SM-BMR2

SM-EW90 A/B 3/5 port

SM-JC40

External Battery

w/ Internal Routing

SM-BTR1

SM-BCR1

SM-BMR2

SM-EW90 A/B 3/5 port

SM-JC41

Internal Battery

w/ Internal Routing

SM-BTR2

SM-BCR2

SM-EW90 A/B 3/5 port

SM-JC41

Battery Mounts:

The SM-BMR2 battery mount is available in three configurations -- Long External, Short External, and Long Internal. Both Long versions are to be mounted using the bottle cage mounts, while the Short version is designed for Di2-specific frames with either a chainstay or down tube mounting location.

Junctions:

There are two junctions needed for completing your Di2 build -- A and B. Junction A, SM-EW90, is located at the handlebars and available in both three- and five-port options. The three-port option is intended for standard shifting with a left and right hand shifter. If you have the intention of using Shimano's satellite sprint shifters, or a combination of time trial shifters and shifter/brake levers, the five-port junction box will be the necessary selection.

Depending on your frame specification, Junction B (SM-JC40 or SM-JC41) is located either internally or externally at the bottom bracket area. Accordingly, SM-JC41 is designed for frames with internal wire routing, while SM-JC40 is intended for external wiring options.

E-Tube Wires:

For your convenience, we've created wire packages for your Di2 build kit in the sizes Small, Medium, and Large. Below, you'll find which wire lengths are included in each kit. Additionally, we've recommended a kit size based on your frame size.

View

It's a most

Familiarity: I've put it through the wringer

Fits great on the bike, connects with no problems. Make sure you use the connecter tool so you don't mess up you cables. Again, its a most, since this is what you need to connect you levers and the rest of the cables to go to your di2 derailleurs and battery. The charging port very easy to access too.

Comment on Juan C G.'s review:

Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

Critical Piece

Familiarity: I've put it through the wringer

Things brings together your Di2 system. The 5-point option is great if you need to install remote shifting at the end of your aero bars. This also hosts your battery warning light. Plug it in once a month or so!

Comment on Hap Seliga's review:

More than just the junction box

Familiarity: I've put it through the wringer

Keep in mind when considering the cost of such a small item that it not only gets the connections made, but also functions as a battery warning light, facilitates micro-adjusting the derailleur positions and is also where you plug in to charge up.